DSD512? PCM768?
The battery-powered iFi Micro iDSD DAC/Heapdhone amp is chock full of functionality. With the ability to play back up to DSD512 as well as PCM files with sample rates to 768kHz and double rate DXD through its dual-core Burr Brown DACs, I'd say the little micro is fairly future proof. Throw in a 8V @ 4000mW output for the headphone jack, and you've got yourself one fulsome package. But that's not all.

photo credit: iFi

The little Micro also adds the iFi iEMatch to better mate your headphones to the iFi's output power, 3D Holographic and XBass for both headphones and speakers, built-in iPurifier® technology (see review), three digital filter choices for PCM (bit-perfect, minimum phase, and standard), three analog filter choices for DSD (Extreme, Extended, Standard Range), and a Coax S/PDIF input/output and Toslink input capable of handling up to 24/192 data. So USB is the obvious connection choice with its DSD and DXD (and super octa-DSD512 and 768kHz PCM) capabilities. The USB connection on the Micro is a type A “OTG” Socket and iFi includes a USB type B to type A “OTG” cable in the package. There's also fixed and variable output, power mode for headphones (Eco, Normal, Turbo), an "Ultra low jitter GMT computer controlled Femto Clock", a polarity switch, 3.5mm input (DAC disabled when in use), a side-mounted USB Type A output for charging your portable devices, and a pocket knife and bottle opener (kidding about those last two).

For the first charge iFi recommends a full overnight charging session. When not is use, you should power the unit off since it does not charge while operating. I mainly used the Micro in fixed output mode fronting my main system connected with a pair of RCA-equipped Auditorium 23 interconnects to the Pass Labs INT-30A driving the DeVore Fidelity The Nines.

There's Nothing Micro About the Micro
Regular readers know that I generally enjoy the sound of iFi's DACs. I reviewed their original iDAC (see review) as well as their nano iDSD DAC (see review) which made it onto AudioStream's short Favorites list. I'm happy to report that the Micro iDSD DAC retains the iFi house sound which is overtly musical to my ears. Compared to the recently reviewed and more expensive Pathos Converto (see review), the iFi is more incisive and more concerned with micro detail and edge. That said, there's nothing abrasive or unnaturally bright about its presentation.

Something like the recent download of the week Our Love from Caribou was very nicely laid out with a sure grip on the beat and bottom end. Acoustic music including Giacinto Scelsi's Suono Rotondo showed off the Micro's way with tone and complex harmonics. While I've heard a richer presentation from the much more expensive Auralic Vega, The Micro delivers a lot of timbral bang for the buck. I did not feel as if I was missing out on anything while listening in enjoyment mode as compared to comparison mode.

Compared to the nano iDSD DAC, the Micro sounds a bit more fuller bodied, more tonally complex and generally more natural. While I'm still a big fan of the little nano especially at its price, the Micro seems to have taken an already good sounding DAC and made it better. Of course a lot of what you're paying for with the Micro is additional functionality and drive for headphone users which is not our focus here so many of the Micro's features are off our beaten path. That said, I did try the Micro with the NAD Viso HP50 'phones and the combo offered a lovely sound picture. Very much like the Micro's analog outputs, listening through headphones proved to be a rich and rewarding experience.

Among the various PCM filters, I found I preferred the Minimum Phase filter as it seemed to present the most balanced and natural sound. The differences between them, however, was subtle. The differences between filter choices for DSD were less subtle and I definitely preferred the "Standard" setting this bringing more color and life to John Coltrane's A Love Supreme in DSD. I also preferred the 3D Holographic enhancer circuit engaged with the 'phones as it brought more dimension and sparkle to the sound. The XBass boost is subtle but I preferred it in the "on" position for headphone use. When listening through speakers, I found I preferred them both set to "off".

There are a number of sonic flavors you can dial in with the iFi Micro DSD. Between the XBass and 3D options, the three filters each for PCM and DSD, the headphone IEM match, the output power settings for the 'phones, not to mention the ability to throw just about any known or unknown file type at it, the Micro has a lot to offer. It's almost too much but that's never really an issue with hi-fi, is it.

I also compared the Direct Output to the Preamplifier mode and found that there was little if any sonic penalty when using the iFi as a preamp. While I prefer using the Pass Labs volume at lower levels and appreciate its remote volume control, I can see some people being perfectly happy using the iFi Micro DSD running direct to a power amp.

Macro Sound for Micro Dollars
OK $500 isn't exactly chump change but the iFi Micro iDSD DAC sure does offer a lot for the money. Of greatest importance beyond all of the bells and whistles is the fact that it makes some nice and natural sounding music you can pass along to your hi-fi or headphones.

I read you're review, and saw that you had different settings when listening via headphones and via speakers. Does the dac sound different versus what you would hear in dac+amp mode? This has a pretty hefty battery in it, so I would think the amp is pretty good, as well.

It is worth noting that 'Bitperfect' or NOS mode, really is true Non-Oversampling for the top 6 bits. The bottom 18 bits are still processed by a third order delta sigma part. NOS is typically limited to 'true PCM' DAC's. But these hybrid Delta-Sigma/ true PCM Dac's from Burr Brown are truly interesting pieces, and Thorsten and crew at iFi have squeezed some very unique functionality out of them.

To my ear, the bitperfect option indeed sounds the best. The 6 most significant bits converted without any oversampling or other DSP makes for the best sound, imo.

…that the Micro iDSD hasn't reached Class B consdering the distance in quality and you mentioning the Nano iDSD being quite close to being Class B. Also, in what aspects would you hear the Halide DAC HD to be better?

Class C! Considering how critical DACs are in your listening chain as well as Audiostream readers in general, I would hope that you remain hyper-critical because to me, yours is one of the two go-to sites for DACs.
I remember you have a ton of "Favourite greatest bits". How do you decide when to use which DAC? Or to put it a bit more cheekily, is there any one (or 2) DACs that you leave in a bit longer?

Michael, I see you stated "I try to compare to similarly priced components." But, if I am to decide to spend $800 retail on a DAC, Powersupply and USB cable I would like to see what a little more money in the used market would get me in comparision. Must like finding a deal on the Mytek Stereo192-DSD DAC. Any comments on the short comings of the iFi Micro iDSD unit compared to those much higher priced DACS?

When both just connected through line outs and using the same filters volume matched, Is the DAC difference still very noticeable when comparing the nano BL and micro BL? Or is it only a bigger difference when going through the headphone amp?